Weasels? Terrible massacre!!!

I am baffled, two nights ago I lost almost 20 chickens. I had about 40 now I have 18 I think. I cam home at 4 am to a massacre! Chickens laying all over the yard, with just one small hole in there head or neck, I found maybe 2 or 3 without heads! I was horrified. I have spent a good bit of money to get silkies and a couple other breeds plus my beloved pets that were just as tame as anything! It was dark when it happened and a few were in the coop, I found small holes in my coop (building flaw) only about 2 inches but it had them pulled down through this small hole. I have have my chickens 3 years and have NEVER lost any to a predator til now. I live in a campground with a creek in the backyard, what could have done this I WANT TO KILL IT! I am crushed, I lost day old peeps a few month old peeps and grow birds. I noticed it comes back for the dead ones and carries them off but the first night it left them all!!!! Help! I have been looking for a trap but nothing has been open this weekend. I have all my chickens that are left locked in the garage now to afraid to put them back in the coop even though i have fixed the holes I found. I am terrified! Do you think this was a weasel? I don't know what has done this!!!

I put bait in the coop last night and it was gone this morning. I fixed up the coop and shut it up but I didn't think of putting bait in tonight, darn, i grilled chicken on the grill tonight will that work?

I would hate to use poison because i have a dog and 3 cats i'm afraid they would get into it. I am gonna bait the coop right now. To make sure holes are little predator proof. Oh in case anyone was wonder the "grilled" chicken was bought from the store lol

That sounds an awful lot like how weasels are supposed to operate, and they can get into some smallish sized holes.

We caught the one we had here in a live trap that was baited with raw beef liver. That said, it was the small sized trap but, even then, hubby had to finagle it to set it to go off at a slightly lesser weight/pressure because when we used it 'as is', the weasel wasn't heavy enough to set it off. Mind you, this had the benefit of a) the weasel being fed (we used a goodly amount of liver!), and so not being as much inclined to go after our chooks, and b) it had him believing that the live trap was a good place to come for food. When the weight on it was reset, we got him almost immediately when he came back for more liver.

FYI, weasel pee smells really bad, and they tend to pee when they are nervous.

We don't have weasels but we have mink that do that.
When building coops around here we make them like Fort Knox. They rarely surface during the day and our dogs would keep them away. They are a fearless predator.
Raccoon trap with a can of sardines in it usually works. Then either let him go far away in the woods or shoot him in the trap.